Molecular Science最新文献_第4页

Time-resolved Photoelectron Imaging Using Ultrashort VUV Pulses 利用超短VUV脉冲进行时间分辨光电子成像

Molecular Science Pub Date : 2018-01-01 DOI: 10.3175/MOLSCI.12.A0097

T. Horio

引用次数: 0

Cooling of Molecular Ions by Recurrent Fluorescence 分子离子的反复荧光冷却

Molecular Science Pub Date : 2018-01-01 DOI: 10.3175/MOLSCI.12.A0100

H. Shiromaru, N. Kono, T. Furukawa, T. Azuma

引用次数: 0

Time- and Space-Resolved Vibrational Spectroscopic Approaches to Elucidate the Behaviors of Complex Molecular Systems: From Biological Cells to Hybrid Solar-Cell Materials: ―細胞からハイブリッド太陽電池材料まで― 时间和空间分辨振动光谱方法阐明复杂分子系统的行为:从生物细胞到混合太阳能电池材料

Molecular Science Pub Date : 2018-01-01 DOI: 10.3175/MOLSCI.12.A0099

Shinsuke Shigeto

{"title":"Time- and Space-Resolved Vibrational Spectroscopic Approaches to Elucidate the Behaviors of Complex Molecular Systems: From Biological Cells to Hybrid Solar-Cell Materials: ―細胞からハイブリッド太陽電池材料まで―","authors":"Shinsuke Shigeto","doi":"10.3175/MOLSCI.12.A0099","DOIUrl":"https://doi.org/10.3175/MOLSCI.12.A0099","url":null,"abstract":"Elucidation of the behaviors of complex molecular systems is central to controlling their elaborate functions. It requires approaches that bear time and space specificities as well as chemical specificity, because various kinds of molecules act at different times and locations in order to carry out particular molecular processes. Timeand spaceresolved vibrational spectroscopies are a powerful method that can meet all of these requirements. This Account shows how these approaches enable us to investigate complex molecular systems including living cells, bacterial communities known as biofilms, and solar-cell materials. Raman microspectroscopy in combination with multivariate data analysis reveals dynamic changes in the concentrations and distributions of cellular components such as proteins and lipids, during the cell cycle without the need for labeling. It is also applied to study bacterial biofilms in a nondestructive manner with a focus on their metabolites (carotenoids in the present case). Nanosecond time-resolved IR spectroscopy is used to observe distinct transient species generated after photoexcitation in organic– inorganic hybrid perovskite solar cells, which are attracting tremendous interest of researchers as a promising next-generation photovoltaic device. The results presented here highlight that deciphering timeand space-resolved vibrational spectra has unraveled a number of new phenomena that are of relevance to biological/material functions.","PeriodicalId":19105,"journal":{"name":"Molecular Science","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81449119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Operando Observation of Liquid and Liquid-Liquid Interface by Soft X-ray Absorption Spectroscopy 软x射线吸收光谱对液体和液-液界面的观测

Molecular Science Pub Date : 2018-01-01 DOI: 10.3175/MOLSCI.12.A0096

M. Nagasaka

{"title":"Operando Observation of Liquid and Liquid-Liquid Interface by Soft X-ray Absorption Spectroscopy","authors":"M. Nagasaka","doi":"10.3175/MOLSCI.12.A0096","DOIUrl":"https://doi.org/10.3175/MOLSCI.12.A0096","url":null,"abstract":"Soft X-ray absorption spectroscopy (XAS) is an element specific method to reveal local structures of liquid samples since soft X-ray below 1 keV has chemically important absorption edges such as C, N, and O K-edges, and L-edges of transition metals. In aqueous solutions, interactions of organic molecules are measured in C and N K-edges and solvent water is separately observed in O K-edge. However, it is difficult to measure XAS of liquid in transmission mode since the thickness of a liquid layer should be less than 1 µm due to large soft X-ray absorption coefficient of liquid. We have successfully developed a liquid flow cell for XAS in transmission mode, where the absorbance of liquid samples can be easily optimized by controlling the liquid thickness. In this review, we report on the temperature dependent change of hydrogen bond in liquid water by O K-edge XAS and intermolecular interactions of pyridine with water in aqueous pyridine solutions at different molar fractions by using XAS in C, N, and O K-edges. For the operando observation of electrochemical reaction, we have developed an electrochemical cell with built-in electrodes and measured Fe L-edge XAS of aqueous iron sulfate solutions during electrochemical reaction under the same scan rate as in cyclic voltammetry. For understanding the phase transition mechanism, not only the mixed phase but also liquid-liquid interfaces after phase transition should be investigated by spatially resolved XAS. We have developed a liquid flow cell that is set in a scanning transmission X-ray microscope. The mechanism of a lower critical solution temperature in aqueous triethylamine solution is studied by spatially resolved XAS of the liquid-liquid interfaces between triethylamine and water phases with the spatial resolution of 140 nm.","PeriodicalId":19105,"journal":{"name":"Molecular Science","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84215521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unoccupied States Measurements, Spatial Mapping, and Nanoscale Structures of Organic Ultrathin Films 有机超薄膜的未占用态测量、空间映射和纳米级结构

Molecular Science Pub Date : 2018-01-01 DOI: 10.3175/MOLSCI.12.A0098

Takashi Yamada

{"title":"Unoccupied States Measurements, Spatial Mapping, and Nanoscale Structures of Organic Ultrathin Films","authors":"Takashi Yamada","doi":"10.3175/MOLSCI.12.A0098","DOIUrl":"https://doi.org/10.3175/MOLSCI.12.A0098","url":null,"abstract":"In this accounts, we summarize recent progress in experimental approaches to the investigation of the unoccupied electronic structures of organic ultrathin films, based on a combination of spectroscopic and microscopic techniques. On the occupied valence bands of the films, it has been extensively studied for a variety of organic molecules. However, systematic investigations of unoccupied electronic states still have been challenging because experimental techniques are limited. In this context, we have clarified the correlation between geometric and electronic structure using a combination of two-photon photoemission (2PPE) spectroscopy and scanning tunneling microscopy (STM). By using 2PPE, one can measure unoccupied states as well as occupied states in the vicinity of the Fermi level. Beyond the diffraction limit of light, STM can be a powerful means of mapping unoccupied electronic structures, not limited to the imaging of geometrical structures. Depending on the molecular density and substrate temperature, organic ultrathin films of polycyclic aromatic hydrocarbons on graphite substrates show a variety of structures, as demonstrated by microscopic observations on the nanoscale. It is apparent that the geometrical structures, especially molecular orientations as stressed throughout this accounts, have a strong impact on both occupied and unoccupied electronic structures. These findings, with a spectroscopic and microscopic understanding at the level of molecule, will provide fundamental insights into desirable electronic properties at organic/substrate interfaces. つ有機超薄膜の表面電子状態を理解することは分子科学と","PeriodicalId":19105,"journal":{"name":"Molecular Science","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75473495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mass Spectrometric Study on Heterogeneous Radical Reactions 非均相自由基反应的质谱研究

Molecular Science Pub Date : 2017-01-01 DOI: 10.3175/MOLSCI.11.A0090

Shinichi Enami

引用次数: 0

Developments on Large-Scale Fine Synthesis Methods for Nanocluster Materials Science 纳米团簇材料科学大规模精细合成方法的研究进展

Molecular Science Pub Date : 2017-01-01 DOI: 10.3175/MOLSCI.11.A0091

H. Tsunoyama

引用次数: 0

Molecular Orbital Imaging by Multi-Dimensional Electron Spectroscopy 分子轨道成像的多维电子能谱

Molecular Science Pub Date : 2017-01-01 DOI: 10.3175/MOLSCI.11.A0093

M. Yamazaki